Which of the following pair of ions have the same number of unpaired electrons

Options

A. `Mn^(2+) and Fe^(2+)`
B. `Mn^(2+) and Fe^(3+)`
C. `Ti^(2+) and Ni^(2+)`
D. `Co^(3+) and Cr^(3+)`

Answer

B, C

Explanation

`Mn^(+2)` and `Fe^(+3)` have 5 unpaired electrons each `: Ti^(+2)` and `Na^(+2)` have 2 unpaired electrons each.